How i can save only limited (say first 100 lines) SOAP UI response in excel sheet using groovy scrip

One option is truncate the response to the maximum number of characters that can saved in Excel, or less.

context.response.take(32000)

https://stackoverflow.com/questions/3226487/how-to-truncate-a-string-in-groovy

Like pretty print?

https://stackoverflow.com/questions/35576317/how-do-i-pretty-print-a-jsonslurper-parse-url-result-of-type-groovy-json-inter

import groovy.json.*
log.info JsonOutput.prettyPrint(context.response)

The script I gave you updates all Test Cases in the same Test Suite (as the script).

You can go one step further out if you want to update all Test Cases in all Test Suites in the current Project:

testRunner.testCase.project.testSuites.each { testSuite ->
 testSuite.value.testCases.each { testCase -> 
  testCase.value.testSteps.each { 
   def testStep = it.value
   if (testStep instanceof com.eviware.soapui.impl.wsdl.teststeps.RestTestRequestStep) { 
    testStep.testRequest.setDiscardResponse(true)
   }
  }
 }
}